The present invention relates to a funnel having an on/off valve or switch. The funnel is of the type having a large upper liquid holding reservoir portion at a funnel inlet and a tapered outlet or discharge tube extending from a base of the reservoir portion and tapering to a funnel outlet.
Many prior approaches to providing funnels with shut off elements have been proposed. However, all known prior approaches are somewhat complex and expensive to manufacture, given that they require the valve or occluding element to have substantial weight or spring pressure to assure a complete seal against a hard-to-manufacture distinct valve seat formed in the inner walls of the funnel device.
One such known funnel is disclosed in U.S. Pat. No. 1,094,098 and features a valve 22 which is raised by wires 23 and 26. A hook portion 28 of wire 26 is brought into engagement with the wall of a container opening to open the valve allowing fluid held in the funnel to pass through the outlet end of a funnel spout into the container. The valve or occluding element 22 of the ""098 patent is mounted in the reservoir portion and its sloping sidewalls must match substantially exactly with the tapered walls of the funnel""s reservoir in order to provide an adequate liquid-tight seal. A further disadvantage of approaches such as disclosed in the ""098 patent is that the liquid in the entire outlet spout of the funnel will drain therefrom even after the occluding valve closes, thereby maximizing spillage of excess fluid when one desires to cease the exit of fluid from the funnel outlet.
Therefore, there is seen to be a need for a simplified occluding element which does not require a separately constructed valve seat to preclude outflow of fluid from the funnel""s outlet end while minimizing escape of excess fluid from the funnel spout once the valve or occluding element has been positioned to halt liquid flow from the funnel.
Another problem with conventional blocking elements in funnel apparatus is the necessity to provide a variety of different type structures for connecting the blocking element to an actuator. Where the actuator and blocking structure combination is not limited in its motion, the blocking element can fall out of the funnel, become jammed, or even lost when the funnel is not in use. Where limited motion is achieved, the connectivity of the blocking element and actuator can be cumbersome and assembly can be difficult. For example, where a blocking plate has to be joined to an actuator structure where the blocking plate and actuator are configured for limited motion, the blocking plate and actuator must be assembled into the funnel area when the connection is to be made. For each connection configuration, there is a tight assembly area, where the funnel provides a restriction. This complicates assembly and drives up the cost of manufacturing the complete funnel, blocking structure and actuator mechanism. This in turn limits the structures and methods of formation and manufacture for the component parts of the completed assembly.
As a result, what is needed is a funnel assembly which can be constructed simply and inexpensively. The method of manufacture and formation of the component parts should enable an inexpensive, stable, and high quality product to be produced.
To meet the above described need, a funnel having a tapered discharge tube of substantially circular cross-section tapering from a tube inlet to a funnel outlet includes a substantially spherical occluding element for placement in the discharge tube, the occluding element having a diameter greater than a diameter of the funnel outlet and less than a diameter of the discharge tube inlet.
In another aspect of the invention, a funnel having a tapered discharge tube of substantially circular cross-section tapers from a tube inlet to a funnel outlet and is equipped with an on/off valve comprising a substantially spherical occluding element for placement in the discharge tube and having a diameter greater than a diameter of the funnel outlet and less than a diameter of the discharge tube inlet. The on/off valve further comprises an occluding element actuator having a first member coupled to the occluding element and extending beyond the funnel outlet when the occluding element is seated in the discharge tube, and a second member coupled to an end of the first member remote from the occluding element and extending toward the discharge tube inlet exteriorly of the discharge tube, and a third member coupled to an end of the second member remote from the first member and extending transversely away from a longitudinal axis of the discharge tube.
The preferred embodiment provides for a final tapered section in the discharge tube to operate as a valve seat and having an angle of about ten degrees from the centerline. The section of funnel above the final taper can have any angle or height but may preferably have an angle of about 25 degrees from the centerline. The higher the height of the main section, the more fluid pressure will brought down upon the valve seat. Consequently, the pressure necessary to operate the spherical element from below will increase.
The use of a tapered section having a circular cross section as a valve seat, in combination with a flow termination occluding element having a spherical surface, provides a system having a stable tangential sealing line despite significant angular displacement of the occluding element and its actuation member. The use of a spherical element in combination with a taper acts to eliminate the possibility of significant surface area contact which could produce jamming. The use of a spherical occluding element in combination with a taper enables a uniform sealing force to be applied between the spherical occluding element and the outlet tube substantially without regard to the angle between the actuator and the longitudinal axis of the discharge tube. Where the taper is about ten degrees, for example, the downward force on the occluding element is translated into multiplier of about 5-6 against the side of the funnel taper. Further, where the material from which at least one of the funnel and the occluding element is made is elastomeric, a single or a mutual accommodation is formed in the material which compensates for non-ideal shapes of the elements. Where the sealing element is not 100% spherical, the taper of the funnel and the force exerted can compensate for it. Similarly where the shape of the taper within the funnel is not 100% round, the force exerted by the occluding element can cause it to compensate.
Another important aspect of the invention is the manner of making it with regard to its simplicity. Other designs have included the necessity of forming a blocking element with a complex manner of attachment to the actuation apparatus. The occluding element of the funnel system of the invention is formable onto the actuation structure outside of its introduction to the tapering section of the funnel. As a result, it can be formed using a multi-piece mold in a configuration in which the funnel main structure is not present to block the action. The actuator may begin as a straight piece of wire, metal, rod, or plastic. In some cases the actuator may start as a pre-formed shape which can be folded to fit through the funnel outlet. Where the actuator is formable, it is dropped through the funnel outlet until the occluding element engages a seat matching a line slightly lower than its median spherical surface, the actuator is formed by bending to an extent sufficient to not allow the actuator and occluding element combination to pass back through the funnel. This keeps the occluding element from becoming lost, and since the occluding element of the invention can tolerate significant pivotal displacement, the structure which exists beneath the funnel outlet need not be concentric with respect to the actuator.